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[Brad Figg <brad.figg@xxxxxxxxxxxxx>]

This bug is missing log files that will aid in diagnosing the problem.
>From a terminal window please run:

apport-collect 1456952

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable
to run this command, please add a comment stating that fact and change
the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the
Ubuntu Kernel Team.

** Changed in: linux (Ubuntu)
       Status: New => Incomplete

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https://bugs.launchpad.net/bugs/1456952

Title:
  support the slub_debug boot option on specific object size

Status in linux package in Ubuntu:
  Incomplete

Bug description:
  [Impact]

  slub_debug cannot work for specific kmem_cache size.

  e. g. slub_debug=PU,kmalloc-1024

  The slub_debug is used to enable the debugging of use-after-free, poison
  overwritten, double free. And it also increases the up time of the server
  when the above mentioned errors happen instead of crashing immediately.

  However, currently, there exists bug that the slub_debug cannot be applied
  for the specific object size. This is not helpful to enable the whole
  system slub_debug because the performance loss will be up to 20%~30%
  according to the customer's measurement. The patch here to limit the
  slub_debug only on the specific object size to alleviate the performance
  loss.

  [Fix]

  The slub_debug=PU,kmalloc-xx cannot work because in the
  create_kmalloc_caches() the s->name is created after the
  create_kmalloc_cache() is called.  The name is NULL in the
  create_kmalloc_cache() so the kmem_cache_flags() would not set the
  slub_debug flags to the s->flags.  The fix here set up a kmalloc_names
  string array for the initialization purpose and delete the dynamic name
  creation of kmalloc_caches.

  [Test case]

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